Fan speed too low. High

Worcester Bosch Fan speed too low. Fault Code

Also written as FANSPEEDTOOLOW — same fault.

The Worcester Bosch Fan speed too low. fault code means: your boiler is struggling to push air through its system because the internal fan is not spinning at the required speed, which prevents it from firing up safely.. It appears on 3 Worcester Bosch models in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Check fan lead and connector, and fan; replace as necessary.
Typical repair cost £200-350 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →
Boiler cover options

Avoid the next call-out bill

A cover plan would handle faults like Fan speed too low.: no call-out fees, no surprise bills.

Approved partner
Domestic Appliance Guard
Unlimited call-outs, 24/7 helpline, no price-hike promise
Get a quote →

Affiliate links. We may earn a commission at no extra cost to you.

Worcester Bosch models that show the Fan speed too low. fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Worcester Bosch Fan speed too low. fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026